scholarly journals Adsorption of Fluoride Ion onto Zirconyl-Impregnated Activated Carbon Prepared from Lapsi Seed Stone

2013 ◽  
Vol 30 ◽  
pp. 13-23 ◽  
Author(s):  
Sahira Joshi ◽  
Mandira Adhikari ◽  
Raja Ram Pradhananga

The potentials of activated carbon derived from Lapsi (Choerospondias axillaries) seed stone after impregnation with zirconium for adsorptive removal of fluoride is presented. Activated carbons from Lapsi seed stone were prepared by three different techniques. Firstly by directly burning in limited supply of air, secondly by treating with a mixture of conc. H2SO4 and HNO3 (in the ratio of 1:1 by weight) and thirdly by activation with zinc chloride (in the ratio of 1:1 by weight) followed by carbonization at 400°C and 500°C under nitrogen atmosphere. Thus prepared carbons were impregnated with zirconyl oxychloride and effects of pH, adsorbent dose, and contact time and adsorbate concentration for the removal of fluoride were evaluated by batch mode. The optimum pH for adsorption of fluoride was observed at pH 3-4, and a minimum contact time for the maximum defluoridation was found to be 180 min. The Langmuir and Freundlich isotherms were used to describe adsorption equilibrium. Zirconium impregnation increased the fluoride adsorption capacity of carbon to considerable extent. Among carbon prepared by three different techniques, the carbon prepared from zinc chloride activation followed by carbonization showed relatively higher fluoride adsorption capacity. From the experiment it is concluded that activated carbon prepared from Lapsi seed is an efficient, low-cost alternative to commercial activated carbon for defluoridation of water.DOI: http://dx.doi.org/10.3126/jncs.v30i0.9330Journal of Nepal Chemical Society Vol. 30, 2012 Page:  13-23 Uploaded date: 12/16/2013    

2019 ◽  
Vol 9 (7) ◽  
Author(s):  
Kamalesh Sen ◽  
Jayanta Kumar Datta ◽  
Naba Kumar Mondal

Abstract In this study, orthophosphoric acid-modified activated char was prepared from Eucalyptus camaldulensis bark (EBAC), and used for removing traces of [N-(phosphonomethyl)glycine] (glyphosate) herbicide from aqueous solution. The adsorption capacity was characterized by zero-point-charge pH, surface analysis, and Fourier transform infrared spectroscopy. Batch mode experiments were conducted to observe the effects of selected variables, namely dose, contact time, pH, temperature, and initial concentration, on adsorption capacity. Langmuir, Freundlich, Temkin, and Dubinin–Radushkevich isotherm models were generated to describe the mechanisms involved in the multilayer adsorption process. The results show that high temperature enhanced the adsorption capacity of EBAC, with a temperature of 373 K yielding adsorption capacity (qmax) and Freundlich parameter (KF) of 66.76 mg g−1 and 9.64 (mg g−1) (L mg−1)−n, respectively. The thermodynamics study revealed entropy and enthalpy of −5281.3 J mol−1 and −20.416 J mol−1, respectively. Finally, glyphosate adsorption was optimized by the Box–Behnken model, and optimal conditions were recorded as initial concentration of 20.28 mg L−1, pH 10.18, adsorbent dose of 199.92 mg/50 mL, temperature of 303.23 K, and contact time of 78.42 min, with removal efficiency of 98%. Therefore, it can be suggested that EBAC could be used as an efficient, low-cost adsorbent for removal of glyphosate from aqueous solutions.


2013 ◽  
Vol 28 ◽  
pp. 94-101 ◽  
Author(s):  
Rajeshwar Man Shrestha ◽  
Raja Ram Pradhananga ◽  
Margit Varga ◽  
Imre Varga

The present study deals with the use of activated carbons prepared from Lapsi seed stone as adsorbents for the removal of Pb (II) ions from aqueous solution. Two series of carbon have been prepared from Lapsi seed stones by treating with conc. H2SO4 and a mixture of H2SO4 and HNO3 in the ratio of 1:1 by weight for removal of metal ions. Chemical characterization of the resultant activated carbon was studied by Fourier Transform Infrared Spectroscopy and Boehm titration which revealed the presence of oxygen containing surface functional groups like carboxylic, lactonic, phenolic in the carbons. The effect of pH and initial metal ion concentration on the adsorption was studied in a batch process mode. The optimum pH for lead adsorption is found to be equal to 5. The adsorption data were better fitted with the Langmuir equations than Freundlich adsorption equation to describe the equilibrium isotherms. The maximum adsorption capacity of Pb (II) on the resultant activated carbons was 277.8 mg g-1 with H2SO4 and 423.7 mg g-1 with a mixture of H2SO4 and HNO3. The waste material used in the preparation of the activated carbons is inexpensive and readily available. Hence the carbons prepared from Lapsi seed stones can act as potential low cost adsorbents for the removal of Pb (II) from water. DOI: http://dx.doi.org/10.3126/jncs.v28i0.8114 Journal of Nepal Chemical Society Vol. 28, 2011 Page: 94-101 Uploaded Date: May 24, 2013


Materials ◽  
2021 ◽  
Vol 14 (22) ◽  
pp. 7045
Author(s):  
Justyna Kazmierczak-Razna ◽  
Anetta Zioła-Frankowska ◽  
Piotr Nowicki ◽  
Marcin Frankowski ◽  
Robert Wolski ◽  
...  

This paper deals with the adsorption of heavy metal ions (Cu2+ and Zn2+) on the carbonaceous materials obtained by chemical activation and ammoxidation of Polish brown coal. The effects of phase contact time, initial metal ion concentration, solution pH, and temperature, as well as the presence of competitive ions in solution, on the adsorption capacity of activated carbons were examined. It has been shown that the sample modified by introduction of nitrogen functional groups into carbon structure exhibits a greater ability to uptake heavy metals than unmodified activated carbon. It has also been found that the adsorption capacity increases with the increasing initial concentration of the solution and the phase contact time. The maximum adsorption was found at pH = 8.0 for Cu(II) and pH = 6.0 for Zn(II). For all samples, better fit to the experimental data was obtained with a Langmuir isotherm than a Freundlich one. A better fit of the kinetic data was achieved using the pseudo-second order model.


Processes ◽  
2021 ◽  
Vol 9 (8) ◽  
pp. 1396
Author(s):  
Gustavo A. Figueroa Campos ◽  
Jeffrey Paulo H. Perez ◽  
Inga Block ◽  
Sorel Tchewonpi Sagu ◽  
Pedro Saravia Celis ◽  
...  

The valorization of coffee wastes through modification to activated carbon has been considered as a low-cost adsorbent with prospective to compete with commercial carbons. So far, very few studies have referred to the valorization of coffee parchment into activated carbon. Moreover, low-cost and efficient activation methods need to be more investigated. The aim of this work was to prepare activated carbon from spent coffee grounds and parchment, and to assess their adsorption performance. The co-calcination processing with calcium carbonate was used to prepare the activated carbons, and their adsorption capacity for organic acids, phenolic compounds and proteins was evaluated. Both spent coffee grounds and parchment showed yields after the calcination and washing treatments of around 9.0%. The adsorption of lactic acid was found to be optimal at pH 2. The maximum adsorption capacity of lactic acid with standard commercial granular activated carbon was 73.78 mg/g, while the values of 32.33 and 14.73 mg/g were registered for the parchment and spent coffee grounds activated carbons, respectively. The Langmuir isotherm showed that lactic acid was adsorbed as a monolayer and distributed homogeneously on the surface. Around 50% of total phenols and protein content from coffee wastewater were adsorbed after treatment with the prepared activated carbons, while 44, 43, and up to 84% of hydrophobic compounds were removed using parchment, spent coffee grounds and commercial activated carbon, respectively; the adsorption efficiencies of hydrophilic compounds ranged between 13 and 48%. Finally, these results illustrate the potential valorization of coffee by-products parchment and spent coffee grounds into activated carbon and their use as low-cost adsorbent for the removal of organic compounds from aqueous solutions.


2018 ◽  
Vol 7 (3.34) ◽  
pp. 449
Author(s):  
S Govindasami ◽  
D Sivakumar ◽  
P B Sakthivel

Recycling and reusing the waste is one of the agenda of sustainable development. Hence this investigation was carried out on utilizing the industrial sludge as activated carbon. The sludge was collected from treatment unit of sugar mill industry, paper mill industry and tannery industry and activated carbon was prepared and named as sugar mill sludge activated carbon (SSAC), paper mill sludge activated carbon (PSAC) and tannery industry sludge activated carbon (TSAC). Batch studies were performed between dye solution and activated carbon to determine adsorption capacity of adsorbent and optimum contact time for the contact process. The optimum contact time and optimum dosage was found to be 120 min and 3.0 g respectively. The maximum adsorption capacity of SSAC, PSAC & TSAC on the concentrations of 10 mg/l of reactive dye solution for the dosage of 3.0 g was 100 %, 92.88 % and 88.54 %. The experimental data and analysis was checked by ANOVA table analysis to justify mathematically. As per ANOVA table the mean performance of SSAC is higher and TSAC is lower. So, finally it is concluded that the experimental results are justified by the ANOVA table analysis on the adsorption capacity of activated carbons.   


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Davidson Egirani ◽  
Mohd T. Latif ◽  
Napoleon Wessey ◽  
Nanfe . R. Poyi ◽  
Nabila Shehata

AbstractTwo forms of activated carbon (i.e., granular and powdered forms) used to test mercury removal in solution. These activated carbons were obtained from the shells of a palmae biomass and used in mercury ion removal in aquatic systems. The African palmae shell taken out from a broadly and simply full-fledged palm tree. This biomass serves as a precursor in the formulation of activated carbons not documented. The powdered and granular fractions of activated carbons described for chemical composition, isoelectric point, and surface area. The mechanism of reactions and the kinetics involved were studied using the results of protonation and rate limitations. The parameters used in the batch mode study included pH, contact time, initial concentration of the adsorbate and the dose of the activated carbons. A comparison of performances, contact time demonstrated the highest adsorption efficiency of 93% for the powdered activated carbon and 92% for the granular activated carbon. The dosage recorded the lowest adsorption efficiency of 84% using granular activated carbon. Comparatively, this study brought to the fore that activated carbon derived from the Plamae biomass remains a novel bio-sorbent


2015 ◽  
Vol 74 (11) ◽  
Author(s):  
Riry Wirasnita ◽  
Tony Hadibarata ◽  
Abdull Rahim Mohd Yusoff ◽  
Zainab Mat Lazim

An oil palm empty fruit bunch-derived activated carbon has been successfully produced by chemical activation with zinc chloride and without chemical activation. The preparation was conducted in the tube furnace at 500oC for 1 h. The surface structure and active sites of activated carbons were characterized by means of Fourier transform infrared spectrometry and field emission scanning electron microscopy. The proximate analysis including moisture content, ash content, bulk density, pH, and pH at zero charge was conducted to identify the psychochemical properties of the adsorbent. The results showed that the zinc chloride-activated carbon has better characteristics compared to the carbon without chemical activation.  


2014 ◽  
Vol 9 (1) ◽  
pp. 166-174 ◽  
Author(s):  
Rajeshwar M. Shrestha ◽  
Margit Varga ◽  
Imre Varga ◽  
Amar P. Yadav ◽  
Bhadra P. Pokharel ◽  
...  

Activated carbons were prepared from Lapsi seed stone by the treatment with H2SO4 and HNO3 for the removal of Ni (II) ions from aqueous solution. Two activated carbon have been prepared from Lapsi seed stones by treating with conc.H2SO4 and a mixture of H2SO4 and HNO3 in the ratio of 1:1 by weight for removal of Ni(II) ions. Chemical characterization of the resultant activated carbons was studied by Fourier Transform Infrared Spectroscopy and Boehm titration which revealed the presence of oxygen containing surface functional groups like carboxyl, lactones and phenols in the carbons. The optimum pH for nickel adsorption is found to be 5. The adsorption data were better fitted with the Langmuir equations than Freundlich adsorption equation to describe the equilibrium isotherms. The maximum adsorption capacity of Ni (II) on the resultant activated carbons was 28.25.8 mg g-1 with H2SO4 and 69.49 mg g-1 with a mixture of H2SO4 and HNO3. The waste material used in the preparation of the activated carbons is inexpensive and readily available. Hence the carbons prepared from Lapsi seed stones can act as potential low cost adsorbents for the removal of Ni (II) from water. DOI: http://dx.doi.org/10.3126/jie.v9i1.10680Journal of the Institute of Engineering, Vol. 9, No. 1, pp. 166–174


2008 ◽  
Vol 5 (4) ◽  
pp. 761-769 ◽  
Author(s):  
S. Madhavakrishnan ◽  
K. Manickavasagam ◽  
K. Rasappan ◽  
P. S. Syed Shabudeen ◽  
R. Venkatesh ◽  
...  

Activated carbon prepared from Ricinus communis Pericarp was used to remove Ni(II) from aqueous solution by adsorption. Batch mode adsorption experiments are carried out by varying contact time, metal-ion concentration, carbon concentration and pH to assess kinetic and equilibrium parameters. The adsorption data were modeled by using both Langmuir and Freundlich classical adsorption isotherms. The adsorption capacity (Qo) calculated from the Langmuir isotherm was 31.15 mg/g of activated carbon at initial pH of 5.0±0.2 for the particle size 125-250 µm.


2015 ◽  
Vol 8 (1) ◽  
pp. 8 ◽  
Author(s):  
Mohamad M. Diémé ◽  
Maxime Hervy ◽  
Saïdou N. Diop ◽  
Claire Gérente ◽  
Audrey Villot ◽  
...  

<p>The objective of this study was to investigate the production of activated carbons (AC) from cashew shells, and millet stalks and their efficiency in fluoride retention. These agricultural residues are collected from Senegal. It is known that some regions of Sénégal, commonly called the groundnut basin, are affected by a public health problem caused by an excess of fluoride in drinking water used by these populations. The activated carbons were produced by a combined pyrolysis and activation with water steam; no other chemical compounds were added. Then, activated carbonaceous materials obtained from cashew shells and millet stalks were called CS-H<sub>2</sub>O and MS-H<sub>2</sub>O respectively. CS-H<sub>2</sub>O and MS-H<sub>2</sub>O show very good adsorbent features, and present carbon content ranges between 71 % and 86 %. The BET surface areas are 942 m² g<sup>-1</sup> and 1234 m².g<sup>-1</sup> for CS-H<sub>2</sub>O and MS-H<sub>2</sub>O respectively. A third activated carbon produced from food wastes and coagulation-flocculation sludge (FW/CFS-H<sub>2</sub>O) was produced in the same conditions. Carbon and calcium content of FW/CFS-H<sub>2</sub>O are 32.6 and 39.3 % respectively. The kinetics sorption were performed with all these activated carbons, then the pseudo-first equation was used to describe the kinetics sorption. Fluoride adsorption isotherms were performed with synthetic and natural water with the best activated carbon from kinetics sorption, Langmuir and Freundlich models were used to describe the experimental data. The results showed that carbonaceous materials obtained from CS-H<sub>2</sub>O and MS-H<sub>2</sub>O were weakly efficient for fluoride removal. With FW/CFS-H<sub>2</sub>O, the adsorption capacity is 28.48 mg.g<sup>-1 </sup>with r² = 0.99 with synthetic water.</p>


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